Siemens 3VA1140-4EE42-0AA0-ZD00 Circuit Breaker, 40A, 36kA @

The Siemens 3VA1140-4EE42-0AA0-ZD00 is a 4-pole IEC frame 160 circuit breaker from the 3VA1 series, rated for line protection with a TM220 thermal-magnetic trip unit. The overload protection Ir is adjustable from 28 A to 40 A, and the short-circuit protection Ii is fixed at 10 x In. Breaking capacity hits 36 kA at 415 V (class S), which means it can safely interrupt fault currents up to that level on a 400 V industrial distribution bus — enough for most secondary panel feeds without cascading upstream. This variant ships with the N conductor unprotected and includes a nut keeper kit, specified for DC Power OEM builds in China. The TM220 trip curve gives a 2:1 Ir range, so a 40 A breaker can be dialed down to 28 A for a 30 A tap — handy when a motor load or small transformer needs tight coordination.